Knowledge Bank

This report gives the computational procedure and the results of a test on the interpolation of deflections from horizontal gravity gradients measured by means of a torsion balance. First, the theory of the interpolation is given together with the description of the associated computer program. Next, the observed data is analyzed, variances are computed or estimated, and interpolations are performed on lines of various lengths. Finally, a detailed local geoid based on the interpolated deflections is compared with the latest (1967) astrogeodetic geoid of the U.S. Army Map Service. The conclusion is that using the torsion balance, deflections can be interpolated to accuracies of about 0'!5 along lines 30-40 km in length.